A known printing apparatus comprises a print station for processing a web by printing an image on the web, a transport device, such as a transport nip, for transporting the web through a transport path along the print station and a support platen facing the print station for supporting the web, when the web is processed by the print station. A pair of side guards is connected to the support platen for guiding the web along the transport path while guarding a respective side edge of the web, i.e. limiting a deformation or protrusion of the side edge of the web away from the support platen. The print station comprises a print assembly movably arranged with the support platen in a direction across the transport path to process the web. The pair of side guards is positioned on the support platen to prevent each side edge of the web from touching the print station, when the web is transported along the print station, as this can damage or pollute the web or the print station.
Each side guard has a fixed shape and is connected to the support platen to fence and accommodate the side edge of the web between a guard portion of the side guard and the support platen, when guiding the web through the transport path. When the side guards are connected to the support platen, the print station, including the print assembly, is arranged at a predetermined gap from the support plate for avoiding that the print station touches the guard portion of the side guards, when the print station is moved across the transport path.
A web to be processed in the printing apparatus may have a varying property, such as varying thicknesses, depending on the web selected. However, the side guards limit a thickness of the web to be processed. Even more, when using a web having a relatively low thickness, a distance between a process surface of the web, which faces the print station, and the print assembly increases as the print station still has to be arranged at the predetermined gap from the support plate for avoiding that the print station collides with the side guards, when the print station is moved across the transport path. As a result, a print quality of the image printed on the relatively thin web may be less than when arranging the print station at a desired distance from the web.
Moreover, a web to be processed may have other varying properties, such as a differing flatness of the web, such as a wavy structure compared to a substantial planar structure of the web.